1. Field of the Invention
This invention relates to a solar heating system for a building of the type which uses air as a heat transfer medium and includes heat collectors with a plurality of covered finned metal heat absorbers over which flows air to be heated and which replace a portion of the roof covering or exterior wall covering.
2. Description of the Prior Art
There have been a considerable number of heating systems proposed that are designed to capture the energy in the sun's rays as a source of heat for a building.
The U.S. Pat. No. 1,801,710, to Abbot, shows an apparatus which includes two sheets of dark coated metal for receiving the sun's rays and with a plurality of oval glass tubes as a cover which permit the sun's rays to pass therethrough but do not readily permit the rays from the metal sheets to be reflected back out.
The U.S. Pat. No. 3,145,707, to Thomason, shows a solar heat collector which includes a box with a transparent protective cover, a layer of insulation on the interior bottom of the box covered by a layer of reflecting foil and a heat collecting sheet with an irregular and blackened upper surface. The heat collecting sheet is covered with a second transparent cover intermediate the sheet and protective cover, is flexible and droops against the heat collecting sheet. Heat absorbing fluid passes between the sheets, and picks up and transfers the heat to the building to be heated.
The U.S. Pat. No. 3,254,643, to Thomason, illustrates a solar heat apparatus which includes a solar heat trap with a hinged reflective cover section 13, insulator and heat conductive corrugated sheet of metal 27 with a vapor barrier 26, supports 28 for supporting the sheet 27 above barrier 26 and transparencies such as glass 31 or plastic 29 spaced thereabove by spacers 30 providing a space for fluid to pass therethrough and absorb the heat.
The U.S. Pat. No. 3,262,493, to Hervey, illustrates a means for heating or cooling a structure which includes a solar heat collector with tubes 34 which have fluid from a heat storage coil passed therethrough for heat transfer.
The U.S. Pat. No. 3,369,539, to Thomason, illustrates a type of solar heat trap which has a transparent outer cover quilted at various intervals and filled with a heat collecting layer of bits of material such as dark sand or similar granular material. The cover is provided with inlets and outlets to permit the passage of heat absorbing fluid therethrough. The material filled bag may be secured to the roof or may be held thereon due to its own weight.
The U.S. Pat. No. 3,841,302, to Falbel, illustrates a solar energy system for a building which system is positioned inside the attic of a building and includes a plurality of reflective surfaces that form a pyramidal reflector which focus the sun's rays on a collector of the flat plate "block" type of collector, and which has a liquid medium such as water in contact therewith which can be used to transfer heat to the inside of the building.
The U.S. Pat. No. 3,859,980, to Crawford, illustrates a solar heating unit which consists of a plurality of tubes in parallel relation connected at their ends to manifolds, with a transparent envelope surrounding the tubes and with a pump to circulate heat absorbing fluid through the tubes for heat transfer to the location to be heated.
The U.S. Pat. No. 4,016,861, to Taylor, shows a solar heat collector which includes a top plate with spaced downwardly extending tabs, a bottom plate with spaced upwardly extending tabs, over which air is circulated and to a heat storage unit. The Taylor structure is unduly complicated with the tab design interfering with the sunlight passage for absorption, does not provide for secure retention of the collector components, is not intended to replace the roof or exterior sheathing on a building and suffers from other shortcomings.
The U.S. Pat. No. 4,029,258, to Groth, shows a solar energy collector with a metal collector plate mounted in a heat insulated space below a dual pane transparent member, air being circulated in the space and to a heat storage unit. The structure of Groth is not suitable for use as a substitute for the roof covering or the exterior wall covering of a building, does not provide the greater surface area of my structure and suffers from other shortcomings.
None of these structures is wholly satisfactory. Those that use a fluid other than air require expensive leakproof piping and an additional heat exchanger inside the building. In addition, none of the structures is easily installed on the exterior of a building and directly thereto and provided with a solar heat collector of sufficient heat input capacity to make the system economically practical for use.
The solar heating system of my invention is readily installed on any new or existing building, uses air as a transfer medium, is provided with solar heat collectors of greater efficiency than those previously available, and includes a heat storage unit which may also pre-heat water for a domestic hot water heater.